Because hyperglycemia has been shown to not significantly influence BOLD signals [66], our data suggest that blunting of the AMPH-induced BOLD response in the DAT-dense striatum of insulin-depleted rats (Figure 5) is not due to STZ-mediated metabolic abnormalities.

To further elucidate the links between the PI3K signaling pathway, DAT function and AMPH action, we activated the PI3K pathway pharmacologically within the striatum of STZ-treated, hypoinsulinemic animals by locally infusing insulin just before the delivery of a brief AMPHpulse in this region.